UK special forces in Afghanistan are parachuting German shepherd dogs with video cameras into Taliban strongholds to search buildings for insurgents, with at least eight animals killed during operations.

The dogs are strapped to the chest of their handlers for the drops, and cameras are attached to their heads to feed back images of buildings and surrounding areas. The tactics have been adapted from US special forces, but the Ministry of Defence said it would not comment on a report on operations by SAS troops.

The dogs are reportedly trained to attack armed people, and eight of them have died in action so far. "But that would be eight SAS men," a source told the Times.

The MoD has an official policy of never commenting on any aspect of any special forces' operation. But that policy has been increasingly undermined by members of the special forces and by comments from ministers and commanders.

As prime minister, Gordon Brown revealed that there were 500 British special forces operating in Afghanistan and Tony Blair praised them in his autobiography, A Journey. General David Petraeus, commander of US and Nato-led forces in Afghanistan, has also praised them.

SAS troops deployed in Iraq, where they were engaged in "kill or capture" missions against al-Qaida insurgents and Saddam Hussein lieutenants, have in the past two years switched to Afghanistan, joining their naval counterparts, the SBS.

They have been carrying out what military sources describe as "decapitation" operations aimed at Taliban commanders in Helmand and Kandahar provinces.

British newspapers reported last month that the SAS was killing Taliban fighters in Helmand on an "industrial scale" with a quarter of senior commanders, several hundred, dead since the spring. Petraeus has said UK and US forces were fighting at an unprecedented tempo in Afghanistan. But some military sources warn that the tactics are leading to Taliban commanders being replaced by younger insurgents, who are less likely to be attracted to possible peace deals.

offerings, and encouragement, by the lure of money, to lay down their arms.

Professor Anthony King, of Exeter University who has been embedded with British forces in Helmand, warned in a recent address to the Chatham House thinktank said that though British special forces had played an important role in Afghanistan, "there has been a tendency for them to operate according to their own kill or capture mandate."

He added: "Given their importance, it is essential that they are the topic of public discussion about British military command".

Campaigners protest use of dogs

Animal rights campaigners expressed their outrage at the use of dogs by British forces in Afghanistan. People for the Ethical Treatment of Animals (Peta) said: "Dogs are not tools or "innovations" and are not ours to use and toss away like empty ammunition shells."

But it's not the first time an army has turned to canine helpers to assist in dealing with an enemy.

In the second world war the Russian military trained dogs to run underneath tanks and armoured vehicles. When faced by attack from the German's Panzer forces the dogs would be sent forward with explosives strapped to their bodies. The detonator was a rod which extended upwards from the explosive pouches the dogs wore. When they ducked under tanks, as they had been conditioned to, the rod would hit the hull of the vehicle, detonating bomb and dog. The anti-tank dogs experienced mixed success. One of the main problems with their deployment was the hounds' tendency to turn tail at the sound of enemy gunfire – they had been trained to run under stationery, non-firing tanks to save fuel and ammunition – and run back to the Soviet trenches, exploding and killing comrades on arrival.

Elephants have been used in combat for over 2,000 years. They are believed to have been first been used in India and Persia, with soldiers armed with spears mounted on the quadrupeds and charging towards their enemy. More recently the elephant has been used in a more passive military sense, to rescue hundreds of refugees fleeing the Japanese invasion of Burma during the second world war. Gyles Mackrell, an English tea-planter, together with a team of elephants and their Indian drivers executed "a sort of far eastern Dunkirk", according to one archivist. The elephants and their drivers crossed the swollen Dapha river and carried hundreds of refugees to freedom.